Merge pull request #211 from alex/stream-ciphers
Document how this returns bytes
diff --git a/cryptography/hazmat/primitives/hmac.py b/cryptography/hazmat/primitives/hmac.py
index 4da0cc3..1457ed7 100644
--- a/cryptography/hazmat/primitives/hmac.py
+++ b/cryptography/hazmat/primitives/hmac.py
@@ -13,47 +13,39 @@
from __future__ import absolute_import, division, print_function
-import binascii
-
import six
+from cryptography.hazmat.primitives import interfaces
+
+@interfaces.register(interfaces.HashContext)
class HMAC(object):
- def __init__(self, key, msg=None, digestmod=None, ctx=None, backend=None):
+ def __init__(self, key, algorithm, ctx=None, backend=None):
super(HMAC, self).__init__()
+ if not isinstance(algorithm, interfaces.HashAlgorithm):
+ raise TypeError("Expected instance of interfaces.HashAlgorithm.")
+ self.algorithm = algorithm
+
if backend is None:
from cryptography.hazmat.bindings import _default_backend
backend = _default_backend
- if digestmod is None:
- raise TypeError("digestmod is a required argument")
-
self._backend = backend
- self.digestmod = digestmod
- self.key = key
+ self._key = key
if ctx is None:
- self._ctx = self._backend.hmacs.create_ctx(key, self.digestmod)
+ self._ctx = self._backend.hmacs.create_ctx(key, self.algorithm)
else:
self._ctx = ctx
- if msg is not None:
- self.update(msg)
-
def update(self, msg):
if isinstance(msg, six.text_type):
raise TypeError("Unicode-objects must be encoded before hashing")
self._backend.hmacs.update_ctx(self._ctx, msg)
def copy(self):
- return self.__class__(self.key, digestmod=self.digestmod,
- backend=self._backend, ctx=self._copy_ctx())
+ return self.__class__(self._key, self.algorithm, backend=self._backend,
+ ctx=self._backend.hmacs.copy_ctx(self._ctx))
- def digest(self):
- return self._backend.hmacs.finalize_ctx(self._copy_ctx(),
- self.digestmod.digest_size)
-
- def hexdigest(self):
- return str(binascii.hexlify(self.digest()).decode("ascii"))
-
- def _copy_ctx(self):
- return self._backend.hmacs.copy_ctx(self._ctx)
+ def finalize(self):
+ return self._backend.hmacs.finalize_ctx(self._ctx,
+ self.algorithm.digest_size)
diff --git a/docs/hazmat/primitives/cryptographic-hashes.rst b/docs/hazmat/primitives/cryptographic-hashes.rst
index a939998..76ca20c 100644
--- a/docs/hazmat/primitives/cryptographic-hashes.rst
+++ b/docs/hazmat/primitives/cryptographic-hashes.rst
@@ -36,6 +36,7 @@
:return: a new instance of this object with a copied internal state.
.. method:: finalize()
+
Finalize the current context and return the message digest as bytes.
Once ``finalize`` is called this object can no longer be used.
diff --git a/docs/hazmat/primitives/hmac.rst b/docs/hazmat/primitives/hmac.rst
index 44cc29f..301d72d 100644
--- a/docs/hazmat/primitives/hmac.rst
+++ b/docs/hazmat/primitives/hmac.rst
@@ -15,10 +15,10 @@
secret key. You can use an HMAC to verify integrity as well as authenticate a
message.
-.. class:: HMAC(key, msg=None, digestmod=None)
+.. class:: HMAC(key, algorithm)
- HMAC objects take a ``key``, a hash class derived from
- :class:`~cryptography.primitives.hashes.BaseHash`, and optional message.
+ HMAC objects take a ``key`` and a provider of
+ :class:`~cryptography.hazmat.primitives.interfaces.HashAlgorithm`.
The ``key`` should be randomly generated bytes and is recommended to be
equal in length to the ``digest_size`` of the hash function chosen.
You must keep the ``key`` secret.
@@ -26,10 +26,10 @@
.. doctest::
>>> from cryptography.hazmat.primitives import hashes, hmac
- >>> h = hmac.HMAC(key, digestmod=hashes.SHA256)
+ >>> h = hmac.HMAC(key, hashes.SHA256())
>>> h.update(b"message to hash")
- >>> h.hexdigest()
- '...'
+ >>> h.finalize()
+ '#F\xdaI\x8b"e\xc4\xf1\xbb\x9a\x8fc\xff\xf5\xdex.\xbc\xcd/+\x8a\x86\x1d\x84\'\xc3\xa6\x1d\xd8J'
.. method:: update(msg)
@@ -39,11 +39,10 @@
:return: a new instance of this object with a copied internal state.
- .. method:: digest()
+ .. method:: finalize()
+
+ Finalize the current context and return the message digest as bytes.
+
+ Once ``finalize`` is called this object can no longer be used.
:return bytes: The message digest as bytes.
-
- .. method:: hexdigest()
-
- :return str: The message digest as hex.
-
diff --git a/tests/hazmat/primitives/test_hmac.py b/tests/hazmat/primitives/test_hmac.py
index 42726a7..a44838c 100644
--- a/tests/hazmat/primitives/test_hmac.py
+++ b/tests/hazmat/primitives/test_hmac.py
@@ -26,32 +26,25 @@
class TestHMAC(object):
test_copy = generate_base_hmac_test(
- hashes.MD5,
+ hashes.MD5(),
only_if=lambda backend: backend.hashes.supported(hashes.MD5),
skip_message="Does not support MD5",
)
def test_hmac_reject_unicode(self, backend):
- h = hmac.HMAC(key=b"mykey", digestmod=hashes.SHA1, backend=backend)
+ h = hmac.HMAC(b"mykey", hashes.SHA1(), backend=backend)
with pytest.raises(TypeError):
h.update(six.u("\u00FC"))
- def test_base_hash_hexdigest_string_type(self, backend):
- h = hmac.HMAC(key=b"mykey", digestmod=hashes.SHA1, backend=backend,
- msg=b"")
- assert isinstance(h.hexdigest(), str)
-
- def test_hmac_no_digestmod(self):
- with pytest.raises(TypeError):
- hmac.HMAC(key=b"shortkey")
-
-
-class TestCopyHMAC(object):
def test_copy_backend_object(self):
pretend_hmac = pretend.stub(copy_ctx=lambda a: True)
pretend_backend = pretend.stub(hmacs=pretend_hmac)
pretend_ctx = pretend.stub()
- h = hmac.HMAC(b"key", digestmod=hashes.SHA1, backend=pretend_backend,
+ h = hmac.HMAC(b"key", hashes.SHA1(), backend=pretend_backend,
ctx=pretend_ctx)
assert h._backend is pretend_backend
assert h.copy()._backend is pretend_backend
+
+ def test_hmac_algorithm_instance(self):
+ with pytest.raises(TypeError):
+ hmac.HMAC(b"key", hashes.SHA1)
diff --git a/tests/hazmat/primitives/test_hmac_vectors.py b/tests/hazmat/primitives/test_hmac_vectors.py
index 27b4501..52d592b 100644
--- a/tests/hazmat/primitives/test_hmac_vectors.py
+++ b/tests/hazmat/primitives/test_hmac_vectors.py
@@ -26,7 +26,7 @@
[
"rfc-2202-md5.txt",
],
- hashes.MD5,
+ hashes.MD5(),
only_if=lambda backend: backend.hashes.supported(hashes.MD5),
skip_message="Does not support MD5",
)
@@ -39,7 +39,7 @@
[
"rfc-2202-sha1.txt",
],
- hashes.SHA1,
+ hashes.SHA1(),
only_if=lambda backend: backend.hashes.supported(hashes.SHA1),
skip_message="Does not support SHA1",
)
@@ -52,7 +52,7 @@
[
"rfc-4231-sha224.txt",
],
- hashes.SHA224,
+ hashes.SHA224(),
only_if=lambda backend: backend.hashes.supported(hashes.SHA224),
skip_message="Does not support SHA224",
)
@@ -65,7 +65,7 @@
[
"rfc-4231-sha256.txt",
],
- hashes.SHA256,
+ hashes.SHA256(),
only_if=lambda backend: backend.hashes.supported(hashes.SHA256),
skip_message="Does not support SHA256",
)
@@ -78,7 +78,7 @@
[
"rfc-4231-sha384.txt",
],
- hashes.SHA384,
+ hashes.SHA384(),
only_if=lambda backend: backend.hashes.supported(hashes.SHA384),
skip_message="Does not support SHA384",
)
@@ -91,7 +91,7 @@
[
"rfc-4231-sha512.txt",
],
- hashes.SHA512,
+ hashes.SHA512(),
only_if=lambda backend: backend.hashes.supported(hashes.SHA512),
skip_message="Does not support SHA512",
)
@@ -104,7 +104,7 @@
[
"rfc-2286-ripemd160.txt",
],
- hashes.RIPEMD160,
+ hashes.RIPEMD160(),
only_if=lambda backend: backend.hashes.supported(hashes.RIPEMD160),
skip_message="Does not support RIPEMD160",
)
diff --git a/tests/hazmat/primitives/utils.py b/tests/hazmat/primitives/utils.py
index efc5fbf..b4a8a3e 100644
--- a/tests/hazmat/primitives/utils.py
+++ b/tests/hazmat/primitives/utils.py
@@ -129,7 +129,7 @@
assert m.finalize() == binascii.unhexlify(md.lower().encode("ascii"))
-def generate_hmac_test(param_loader, path, file_names, digestmod,
+def generate_hmac_test(param_loader, path, file_names, algorithm,
only_if=None, skip_message=None):
def test_hmac(self):
for backend in _ALL_BACKENDS:
@@ -138,7 +138,7 @@
yield (
hmac_test,
backend,
- digestmod,
+ algorithm,
params,
only_if,
skip_message
@@ -146,18 +146,15 @@
return test_hmac
-def hmac_test(backend, digestmod, params, only_if, skip_message):
+def hmac_test(backend, algorithm, params, only_if, skip_message):
if only_if is not None and not only_if(backend):
pytest.skip(skip_message)
msg = params[0]
md = params[1]
key = params[2]
- h = hmac.HMAC(binascii.unhexlify(key), digestmod=digestmod)
+ h = hmac.HMAC(binascii.unhexlify(key), algorithm)
h.update(binascii.unhexlify(msg))
- assert h.hexdigest() == md
- digest = hmac.HMAC(binascii.unhexlify(key), digestmod=digestmod,
- msg=binascii.unhexlify(msg)).hexdigest()
- assert digest == md
+ assert h.finalize() == binascii.unhexlify(md.encode("ascii"))
def generate_base_hmac_test(hash_cls, only_if=None, skip_message=None):
@@ -173,11 +170,11 @@
return test_base_hmac
-def base_hmac_test(backend, digestmod, only_if, skip_message):
+def base_hmac_test(backend, algorithm, only_if, skip_message):
if only_if is not None and not only_if(backend):
pytest.skip(skip_message)
key = b"ab"
- h = hmac.HMAC(binascii.unhexlify(key), digestmod=digestmod)
+ h = hmac.HMAC(binascii.unhexlify(key), algorithm)
h_copy = h.copy()
assert h != h_copy
assert h._ctx != h_copy._ctx